Our preliminary studies indicated that a small population of octamer-binding transcription factor 4 (OCT4)-positive cancer cells was present in ECC tissues and that ECC with a high percentage of OCT4-positive cells displayed rapid progression, high incidence of lymph node metastasis, and short tumor-free survival and overall survival [2]. Here, POU5F1 is linked to metastatic malignant neoplasm in the lymph nodes.